Contraceptive caps and diaphragms are barrier methods of birth control that are slightly different but work in similar ways.

A diaphragm is a shallow latex dome that fits inside a woman’s vagina. It works by covering the cervix and surrounding area and preventing sperm from passing into the uterus (womb) and fertilising the egg. It is usually used with spermicide gel that kills sperm on contact.

How effective are diaphragms?

How effective are diaphragms?

Most women can use a diaphragm however, because they work by covering the cervix, anything that prevents them from fitting properly will make them less effective. A diaphragm may not be suitable for you if:

  • you have an unusual shaped cervix
  • you can’t reach your cervix (this feels like a hard bump inside your vagina)
  • you have weak vaginal muscles (perhaps from giving birth)
  • you are allergic to latex or spermicide
  • you have a vaginal infection
  • you have multiple sexual partners

When you visit a Devon Sexual Health clinic you can chat with your doctor or nurse and they will be able to give you advice about the best form of contraception for you.

Are there any side effects?

Are there any side effects?

There are not usually any side effects associated with the diaphragm as a form of contraception. Occasionally some people may be allergic to latex or spermicide and occasionally they can cause cystitis (a bladder infection). It is really important to remember that the diaphragm cannot prevent sexually transmitted infections STIs.

Where can I get a diaphragm?

Where can I get a diaphragm?

You can get a cap or a diaphragm from your nearest Devon Sexual Health clinic. We have regular drop in clinics or to avoid waiting you can book an appointment.

What happens when you get a diaphragm fitted?

What happens when you get a diaphragm fitted?

A specially trained doctor or nurse will have a chat with you about your sexual history, your health and what will work best for you and your lifestyle. If a diaphragm is a good option for you, they will give you a quick examination to see what size you will need. They will then show you how to apply spermicide and how to fit it, so that it is in the right place and working effectively.

We will probably ask you to come back, with your diaphragm fitted, for a check-up.

Pros & Cons

Pros & Cons

  • There are no side effects
  • You only need to put it in when you are going to have sex
  • You can put it in at a convenient time before sex (more than 3 hours and you need to apply extra spermicide)
  • It’s not as effective as other forms of contraception
  • You need to learn how to use it properly
  • You need to remember / stop and fit it before having sex
  • It does not protect against STIs
How can we help you?

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Accessing our service during the COVID pandemic

How to access our service:

We have now implemented a telephone triage system for all of our clinics. This system will be in place for the duration of the pandemic. Please contact our services to access this triage system. Our central telephone number is 0300 303 3989.

If you are experiencing symptoms of Coronavirus please do not attend the clinic. Clear advice for people with symptoms of coronavirus is available at nhs.uk/coronavirus .

Advice from our service:

We have updated information on the provision of routine contraception during this pandemic here.

If you need the combined contraceptive pill please try (if you can) to get updated measurements of your height, weight and blood pressure before calling us.

We are currently prioritising these groups for coil and implant (LARC) fits:

  • Those with vulnerabilities including but not limited to those who are: <18, attending abortion and maternity services, homeless, sex workers, victims of sexual assault, people with language barriers, drug and alcohol problems, learning disability, serious mental illness
  • Those aged <30 years

More details on LARC fittings at our service are found here

There is also specific advice on coronavirus available for People Living with HIV here, and for pregnant women here

Self-requested Sexual Health screening by post is available for for under 25s only - more info here

For others with testing requirements please contact the service on 0300 303 3989.

Information is now also available to advise on sexual contact during a time of social distancing here.

Alternative provision:

Please be aware that we may have to cancel, rearrange or shut clinical services in response to changing clinical and staffing pressures created by the Coronavirus pandemic. 

If you are struggling to access sexual health services, alternatives may be available:

  • Emergency Contraception - at your local pharmacy - more info
  • Contraceptive pills and LARC procedures - obtained from your GP
  • HIV postal testing - available to at-risk groups for a small fee -  more info
  • HIV PEPSE - available via A+E departments - more info
  • Condoms by post (for gay and bisexual men only) - more info